1. Field of the Invention
The present invention relates to an adjustment drive, in particular a window winder drive of a motor vehicle, having an electric motor with a brush system.
2. Description of the Background Art
Motor vehicles usually have adjustment parts, for example side windows and/or a sliding roof, which can be opened or closed by means of an electromotive adjustment drive. The respective adjustment part is mounted on the motor shaft by means of a gear mechanism which is driven by an electric motor, in particular a worm gear mechanism having an (output-drive-side) worm gear and a (drive-side) worm. The gear mechanism is conventionally arranged in a gear mechanism housing to which the electric motor is attached, for example by means of a holder. The electric motor is usually attached to the gear mechanism housing at its end side, wherein an axial pin, that is to say that region of the motor shaft with which the gear mechanism engages or the gear mechanism drive part (shaft-end-side worm) of the electric motor, is situated within the gear mechanism housing.
Plug contacts which are electrically connected to corresponding mating contacts, which are arranged in the gear mechanism housing, are additionally located at the end side of the electric motor. The plug contacts are arranged in an interlocking manner in a main body of the electric motor, which main body is conventionally produced from plastic, and are secured against slipping or sliding by means of structures. In a known embodiment, the structures of the plug contacts are in the form of saw teeth or fir trees and, by means of the teeth which act as barbs, prevent displacement of the plug contacts both during assembly and during operation of the drive. During production of the electric motor, the plug contacts are encapsulated with the plastic of the main body and therefore the interlocking connection between said plug contacts and main body is established.
An electronics system which is usually arranged in the gear mechanism housing makes electrical contact with the mating contacts. In this case, the electronics system controls a flow of electrical energy via the mating contacts to the electric motor. Furthermore, the electronics system usually has a trapping prevention means for preventing trapping situations during operation of the adjustment drive.
U.S. 2009/0121578 A1 discloses an adjustment drive having a worm gear mechanism and having an electric motor with brushes. The brush system has a contact for electrical connection in the form of a press fit or a close fit, wherein the contact is mechanically uncoupled from the gear mechanism housing in order to prevent vibrations.